Medial Patellofemoral Ligament Reconstruction for Knee Dislocation

(SHYFT Trial)

Overseen By Sarah Kerslake, BPhty

Age: < 65

Sex: Any

Trial Phase: Academic

Sponsor: Banff Sport Medicine Foundation

Disqualifiers: Trochlear dysplasia, Osteoarthritis, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 6

Duration: Immediate post-operative period

32 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores two approaches to addressing knee dislocation issues caused by patellofemoral instability (when the kneecap frequently shifts out of place). Researchers compare standard knee ligament reconstruction with a combined approach that includes an additional bone adjustment procedure. The goal is to determine which method better improves knee stability and patient satisfaction. Individuals with frequent kneecap dislocations might be suitable candidates for this study. As an unphased trial, it offers patients the chance to contribute to innovative research that could enhance future treatment options.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What prior data suggests that this technique is safe for knee dislocation?

Research has shown that surgery to repair the ligament on the inside of the knee (MPFL-R) is generally safe and well-tolerated. In past studies, only about 10.6% of patients experienced minor issues, such as mild knee pain, lingering instability, and a few minor infections.

When combined with tibial tubercle osteotomy (TTO), studies found similar safety outcomes. Adding TTO did not introduce major new safety concerns compared to MPFL-R alone. Overall, both treatments are considered safe for individuals with knee dislocation problems. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Medial patellofemoral ligament reconstruction (MPFL-R) is unique because it specifically targets the stability of the kneecap, which is crucial for preventing dislocations. Unlike traditional treatments that often rely on physical therapy or bracing, MPFL-R surgically restores the ligament that naturally helps keep the kneecap in place. Researchers are particularly excited about the MPFL-R combined with tibial tubercle osteotomy (TTO) because this combined approach addresses both the soft tissue and structural alignment issues, potentially offering a more comprehensive solution to knee instability. This could lead to better long-term outcomes for patients with knee dislocations compared to current standard treatments.

What evidence suggests that this trial's treatments could be effective for knee dislocation?

This trial will compare two treatment approaches for knee dislocation. Research has shown that reconstructing the medial patellofemoral ligament (MPFL-R), one of the treatments in this trial, effectively stabilizes the knee and prevents the kneecap from slipping out of place. Studies have found that the chance of the kneecap dislocating again is as low as 1%, and the chance of the surgery not working is about 6.6%. Patients typically experience improved knee function and less pain after the surgery.

Another treatment arm in this trial involves MPFL-R combined with a procedure called tibial tubercle osteotomy (TTO). This combination often leads to better results for those with ongoing kneecap dislocation issues. The combined approach has a higher success rate without increasing the risk of complications. However, some studies found no major difference in patient satisfaction when comparing the combined surgery to MPFL-R alone. ^{1 2 5 6 7}

Who Is on the Research Team?

Laurie A Hiemstra, MD, PhD

Principal Investigator

University of Calgary

Are You a Good Fit for This Trial?

This trial is for young people aged 13-30 with recurrent knee cap dislocation and specific bone alignment issues (TT-TG ≥15mm on MRI or ≥18mm on CT). They must have mature bones, confirmed by x-rays. It's not for those with certain knee ratios, excessive femoral or tibial rotation, severe groove deformities needing surgery, advanced arthritis in the kneecap joint, cartilage restoration procedures, inability to do computer questionnaires or if pregnant.

Inclusion Criteria

I am between 13 and 30 years old.

My kneecap frequently dislocates causing pain.

TT-TG ≥15mm measured on MRI or ≥18mm on CT scan

Exclusion Criteria

I have moderate to severe knee arthritis confirmed by an X-ray.

I need surgery for a severe knee cap alignment issue.

Caton-Deschamps ratio ≥ 1.4 on lateral radiographs

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo either isolated MPFL-R or MPFL-R with TTO surgery

Immediate post-operative period

Follow-up

Participants are monitored for safety and effectiveness after treatment, with assessments at 6, 12, and 24 months post-operative

24 months

Multiple visits at 6, 12, and 24 months post-operative

Long-term Follow-up

Participants continue to be monitored for long-term outcomes and complications

Beyond 24 months

What Are the Treatments Tested in This Trial?

Interventions

• Medial patellofemoral ligament reconstruction

Trial Overview The study tests whether adding a bone realignment procedure (tibial tubercle osteotomy) to a ligament reconstruction surgery improves outcomes in patients with misaligned knees causing instability. This pilot randomized controlled trial will check how feasible it is to recruit participants and follow them up at least one year after surgery.

How Is the Trial Designed?

Group I: MPFL-R Active Control 1 Intervention

Medial patellofemoral ligament reconstruction

Group II: MPFL-R + TTO Active Control 2 Interventions

Medial patellofemoral ligament reconstruction with concomitant tibial tubercle osteotomy

Medial patellofemoral ligament reconstruction is already approved in European Union, United States, Canada for the following indications:

Approved in European Union as MPFL reconstruction for:

• Patellar instability
• Recurrent patellar dislocation

Approved in United States as MPFL reconstruction for:

• Patellar instability
• Recurrent patellar dislocation

Approved in Canada as MPFL reconstruction for:

• Patellar instability
• Recurrent patellar dislocation

Who Is Running the Clinical Trial?

Banff Sport Medicine Foundation

Lead Sponsor

Trials

4

Recruited

160+

ConMed Corporation

Industry Sponsor

Trials

9

Recruited

800+

CONMED Corporation

Industry Sponsor

Trials

11

Recruited

1,100+

Canadian Orthopaedic Foundation

Collaborator

Trials

15

Recruited

1,900+

Published Research Related to This Trial

In a study of 65 patients undergoing MPFL reconstruction for recurrent patellar dislocation, there were no reported episodes of dislocation or subluxation after surgery, indicating high effectiveness of the procedure.

Patients showed significant improvements in knee function, with Lysholm scores increasing from 60.6 to 89.8, Tegner scores from 3.6 to 5.6, and IKDC scores from 40.0 to 82.0, demonstrating both safety and efficacy of the surgical intervention.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Reconstruciton of medial patellofemoral ligament (MPFL) for the treatment of recurrent patellar dislocation]. Yun, XD., Xia, YY., Wu, M., et al.[2022]

MPFL reconstruction effectively reduces lateral tracking of the patella, which is important for preventing instability, but errors in femoral fixation and graft tension can lead to overcorrection and increased pressure on the medial patellar cartilage.

Simulations showed that nonanatomic femoral attachment and decreased graft length resulted in significant increases in medial pressures, indicating that precise surgical techniques are crucial to avoid complications such as loss of knee flexion and cartilage overload.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dynamic Simulation of the Effects of Graft Fixation Errors During Medial Patellofemoral Ligament Reconstruction. Elias, JJ., Kelly, MJ., Smith, KE., et al.[2020]

MPFL reconstruction is a new surgical method aimed at treating recurrent patellar instability and dislocation, but the radiologic outcomes post-surgery are not well documented in current literature.

The study reviews the anatomy and biomechanics of the MPFL and highlights imaging findings and potential complications following double-bundle MPFL reconstruction, emphasizing the need for better understanding of post-operative results.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MRI evaluation and complications of medial patellofemoral ligament reconstruction. Torabi, M., Wo, S., Vyas, D., et al.[2022]

In a study of 26 patients who experienced patellar redislocation after MPFL reconstruction, 69% of the cases were nontraumatic, indicating that underlying anatomical risk factors may play a significant role in these failures.

Half of the patients had nonanatomic femoral tunnel positions, and 65% had two or more anatomical risk factors, such as trochlear dysplasia and valgus malalignment, suggesting that careful preoperative assessment and precise surgical technique are crucial for successful outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Failure Analysis in Patients With Patellar Redislocation After Primary Isolated Medial Patellofemoral Ligament Reconstruction. Feucht, MJ., Mehl, J., Forkel, P., et al.[2022]

The study identified the most isometric attachment point for medial patellofemoral ligament (MPFL) reconstruction, which is located posterior and proximal to the anatomic femoral MPFL attachment, showing only a 4% length change during knee flexion.

It was found that improper positioning of MPFL tunnels, particularly proximal and anterior placements, can lead to significant changes in ligament length during movement, emphasizing the need for precise graft placement to reduce complications like recurrent instability.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Medial Patellofemoral Ligament Is a Dynamic and Anisometric Structure: An In Vivo Study on Length Changes and Isometry. Kernkamp, WA., Wang, C., Li, C., et al.[2020]

In a study of 19 young patients who underwent revision surgery after unsuccessful medial patellofemoral ligament (MPFL) reconstruction, the main reasons for failure included not addressing additional risk factors, technical errors during surgery, and poor patient selection.

Post-revision, patients showed significant improvements in knee function and satisfaction, with median Kujala scores rising from 57 to 83 and 78.9% reporting satisfaction, indicating that revision surgery can be effective despite initial complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Analysis of failure and clinical outcome after unsuccessful medial patellofemoral ligament reconstruction in young patients. Nelitz, M., Williams, RS., Lippacher, S., et al.[2022]

In a study of 23 patients undergoing MPFL reconstruction for recurrent patellar dislocation, no recurrences were reported, indicating the procedure's efficacy in preventing dislocation.

The study found that the cross-sectional area of the femoral tunnel aperture increased by 41.1% over one year, with significant anterior migration of the tunnel, particularly influenced by patella alta, but not by other assessed risk factors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

3D Computed Tomography Evaluation of Morphological Changes in the Femoral Tunnel After Medial Patellofemoral Ligament Reconstruction With Hamstring Tendon Graft for Recurrent Patellar Dislocation. Kita, K., Tanaka, Y., Toritsuka, Y., et al.[2018]

The medial patellofemoral ligament (MPFL) is crucial for knee stability, and its reconstruction (MPFLR) is recommended primarily for patients with a history of multiple patellar dislocations after conservative treatments fail.

Current literature lacks definitive comparisons of surgical techniques for MPFLR, making it essential to carefully evaluate candidates to minimize risks and ensure effective outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MPFL reconstruction: indications and results. Dall'Oca, C., Elena, N., Lunardelli, E., et al.[2023]

A novel MRI technique was developed to measure the distance from the Schöttle point to the medial distal femoral physis in 34 skeletally immature patients with patellar instability, revealing an average distance of 7.27 mm, which is crucial for safe MPFL reconstruction.

The study found that the Schöttle point is consistently located distal to the medial distal femoral physis, and females were closer to the Schöttle point than males, suggesting that surgical planning may need to account for these anatomical differences to avoid complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Simple Method of Measuring the Distance From the Schöttle Point to the Medial Distal Femoral Physis With MRI. Bishop, ME., Black, SR., Nguyen, J., et al.[2022]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4570947/

Medial Patellofemoral Ligament Reconstruction MPFL reconstruction is effective for stabilizing the knee and may alone prevent lateral patellar dislocation.

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5502077/

Outcomes After Isolated Medial Patellofemoral Ligament ... Recent reviews by Tompkins and Arendt and Matic et al have reported redislocation and failure rates of 1% and 6.6%, respectively, after MPFL reconstruction.

3. orthopedicreviews.openmedicalpublishing.org orthopedicreviews.openmedicalpublishing.org/article/138208-a-landscape-of-recent-literature-on-the-predictors-of-success-and-failure-in-medial-patellofemoral-ligament-reconstruction

A Landscape of Recent Literature on the Predictors ... The aim of this review is to identify the factors that predict both the success and failure of MPFL reconstruction in the treatment of patellofemoral ...

4. sciencedirect.com sciencedirect.com/science/article/pii/S0968016023001783

Medium-term outcome of medial patellofemoral ligament ... We found a statistically significant improvement in mean Kujala and Oxford knee scores (P < 0.001) postoperatively. No major complications such as knee ...

5. ijspt.scholasticahq.com ijspt.scholasticahq.com/article/141128

Current Concept Review: Medial Patellofemoral Ligament ... Among surgical management options, MPFL reconstruction is an effective procedure with demonstrated improvements in clinical and functional ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11656640/

Operative Repair of Medial Patellofemoral Ligament Injury ... This review aims to systematically evaluate and compare the clinical outcomes of operative repair via MPFL reconstruction versus conservative ...

7. nature.com nature.com/articles/s41598-023-40610-x

Medium to long-term outcomes of medial patellofemoral ... Medium to long-term outcomes of medial patellofemoral ligament reconstruction using the superficial quadriceps versus a hamstring autograft in ...